our virtual learning space

assessing fluid status

lelaneemeollamokowich — Tue, 06 May 2008 08:30:14 +0000

central venous pressure
capillary refill time
pulse rate
blood pressure
urine output
skin turgor
mucous membrane
sunken eyes
decreased GCS

hypoxia – where is the underlying problem

lelaneemeollamokowich — Tue, 06 May 2008 08:06:37 +0000

respiratory centres – brainstem, cerebral lesions
phrenic nerve – diaphragm muscles
spinal nerve – intercostal muscles
ventilation
perfusion – PE, pneumonia (vasoconstriction in response to hypoxia)
diffusion – 1. surface area (emphysema); 2. nature of membrane (pulmonary oedema, fibrosis, atelectasis); 3. diffusion gradient
intrapleural – inflammatory, infective

post extubation x-ray

lelaneemeollamokowich — Tue, 06 May 2008 08:00:39 +0000

rationale

collapse of lung
consolidation
sputum

post-extubation, ventilation is dependent on patient’s respiratory abilities. respiratory exchange problems can be masked by intubation and manifest post-extubation (if lesions not resolved)

central line – why is it bad to have it put right into RA

lelaneemeollamokowich — Tue, 06 May 2008 07:58:05 +0000

irritation of RA –> AF
erosion of RA
tricuspid valve damage
endocarditis (if unsterile)

central line – where should the tip be?

lelaneemeollamokowich — Tue, 06 May 2008 07:56:28 +0000

halfway between aortic knuckle

causes of pulseless electrical activity (PEA) / electrical-mechanical dissociation (EMD)

lelaneemeollamokowich — Tue, 06 May 2008 07:53:09 +0000

Pulseless electrical activity (PEA) / electrical-mechanical dissociation (EMD) = presence of ecg trace but no cardiac output (hence pulseless)

Causes – 5H, 4T

Hypokalaemia
Hypovolaemia
Hypoglycaemia
Hypoxia
Hypothermia

Tamponade
Tension pneumothorax
Thromboembolism
Toxins

complications of blood transfusion

lelaneemeollamokowich — Tue, 06 May 2008 07:45:06 +0000

bacteria infection
viral infection (hep C 1in400; HIV 1in1million)
prion disease
malaria

transfusion related acute lung injury
transfusion related immune modulation (cytokines released by white cells)
blood group mismatch (ABO incompatibility)
anaphylaxis

hypercalcaemia (citrate binds to Ca++)
hyperkalaemia (transfusion of loads of old blood)
preservatives (leading to acidosis)
hyperthermia (?)

Hb can poison kidneys
coagulopathy
fluid overload

what’s leaking from the nose? differentiating between CSF from other secretions

lelaneemeollamokowich — Tue, 06 May 2008 07:34:00 +0000

double ring sign – place 1ml of fluid on absorbent filter paper; if csf = central circle of blood and outer clear ring of csf
dipstick – absence of glucose excludes csf (presence of glucose is not diagnostic since nasal secretion and tear contain glucose as well). presence of protein

note:

csf -

protein 20-40mg/dL; glucose 50-100mg/dL

base of skull fracture

lelaneemeollamokowich — Tue, 06 May 2008 07:27:42 +0000

clinical features

periorbital bruising (racoon’s eyes)
haemotympanum (blood leaking from ear) or otorrhoea (CSF leaking from ear)
mastoid bruising (battle’s sign)
rhinorrhoea (CSF from nose)

positive end-expiratory pressure

lelaneemeollamokowich — Tue, 06 May 2008 07:22:17 +0000

Good/importance

decreases preload (if hypervolaemic)
prevent alveolar collapse
decreases work of inspiration (since alveolar is opened)
prolong alveolar opening time (hence increase time for gaseous exchange)

Bad

decreases venous return (nil PEEP if hypovolaemic)
high PEEP associated with barotrauma

ventilation without PEEP is bad

ventilation with high PEEP is bad